Shotgun shell wad

ABSTRACT

A wad for a shotgun shell comprising a polyethylene unit having an obturator wad connected to a shot pouch by a generally helically extending compression spring member, the flights of which are maintained in spaced relation by axially extending strut members arranged to cause the spring member to increase in radial dimensions when compressed in an axial direction and thereby scrub the barrel interior as it leaves the latter upon firing of the shell.

United States Patent Merritt May 16, 1972 4] SHOTGUN SHELL WAD Primary Examiner-Robert F. Stahl [72] Inventor: Edward E. Merritt, Anoka, Minn. Attorney schmeder siegried & Ryan [73] Assignee: Federal Cartridge Corporation, Minneapolis. Minn. [57] ABSTRACT [22] Filed: Nov. 4, 1970 Appl. No.: 86,687

A wad for a shotgun shell comprising a polyethylene unit having an obturator wad connected to a shot pouch by a generally helically extending compression spring member, the flights of which are maintained in spaced relation by axially extending strut members arranged to cause the spring member to increase in radial dimensions when compressed in an axial direction and thereby scrub the barrel interior as it leaves the latter upon tiring of the shell.

30 Claims, 9 Drawing Figures SHOTGUN SHELL WAD This invention relates to shotgun shell wads. More particularly, it relates to a unitary wad which covers the propellant and holds the shot while sealing the one from the other and having an inherent cushion and scrubbing efiect upon firing of the shell.

It is a general object of my invention to provide a novel and improved wad for a shotgun shell of inexpensive but effective construction to be disposed between the propellant and shot load.

A more specific object is to provide a novel and improved wad for a shotgun shell which will effectively seal the propelling gases, protect the shot against barrel erosion, and will provide a cushion against the shock of firing.

Another object is to provide a novel and improved wad which will have structural characteristics such as to exhibit a sufficiently variable wad length to permit several different loads to be loaded with the same wad size and provide a scrubbing action to the barrel wall to limit and minimize lead or powder fouling.

Another object is to provide a novel and improved wad for a shotgun shell which will provide improved scrubbing actions upon the interior of the barrel upon firing of the shell.

Another object is to provide a novel and improved combined obturator wad and shot cup which can be molded inexpensively in a single piece unit with cam operated molds.

These and other objects and advantages of my invention will more fully appear from the following description, made in connection with the accompanying drawings, wherein like reference characters refer to the same or similar parts throughout the several views, and in which:

FIG. 1 is a vertical sectional view of a shotgun shell utilizing one of my wads with the spring portion of the wad shown in side elevation;

FIG. 2 is a horizontal sectional view taken through the wad shown in FIG. 1 on approximately line 2--2 thereof;

FIG. 3 is a side elevational view of the wad shown in FIG. 1 in unloaded condition, with portions thereof broken away;

FIG. 4 is a plan elevational view of the wad shown in FIG. 3;

FIG. 5 is a side elevational view of the wad shown in FIG. 3 taken at a 90 angle from that shown in FIG. 3;

FIG. 6 is a horizontal sectional view taken approximately along line 6--6 ofFIG. 5;

FIG. 7 is a horizontal sectional view taken approximately along line 77 of FIG. 5;

FIG. 8 is a side elevational view of the wad shown in FIG. 3, but modified to illustrate the distortion thereof which takes place when the wad is subjected to shell firing conditions; and

FIG. 9 is a side elevational view of an alternate form of the invention.

The preferred embodiment of my invention is shown in FIG. 1-8 inclusive. Referring to the drawings, FIG. 1 shows an elongated tubular shot shell casing 11 made of plastic, although paper, metal, or any other suitable material may also be used. A metal head or base 12 is attached to the lower end of the tubular casing 11 by any well-known means and has a primer means 13 mounted therein. Base wad 14 provides the necessary protection to the metal base 12 from the explosive gases generated by the ignition of the propellant l5.

Adjacent to the propellant 15 and bearing thereagainst is a combination wad column-shot cup 10, made preferably of plastic. This wad 10 separates the shot charge 18 from the propellant l5 and seals the gases behind it while containing the shot and protecting the same against deformation by the gun barrel, as they are projected therefrom by the ignited propellant. The forward end of the casing 11 is crimped as at 19 to form a shot retaining closure 20 prior and up to the firing of the shell.

The wad 10 includes an obturator member 21 which consists of an annular disc that merges into a depending peripheral flange 22. As best shown in FIG. 3, this peripheral flange tapers in thickness toward its free end and surrounds the upper portion of the propellant 15 as best seen in FIG. 1. The undersurface of the obturator member 21 bears against the upper surface of the propellant l5.

Formed integrally with the obturator member 21 and extending upwardly therefrom is a generally helically extending compression spring member 23. The flights 24 of the spring member 23 define a modified helix and extend upwardly from the obturator member 21 and terminate at and merge into an annular shot supporting member 25. An upstanding tubular wall 26 forms a shot cup with the shot supporting member 25 and is a part thereof. As best seen in FIG. 3, the opposite ends of the generally helical spring member 23 merge gradually with and are a part of the obturator member 21 and the shot supporting member 25. The entire wad 10 is preferably manufactured as a single unitary item from polyethylene, and, in the shape shown, can be molded relatively inexpensively with cam operated molds.

Extending between the flights 24 of the generally helical compression spring member 23 is a plurality of sets of generally axial extending strut members. These strut members connect the flights of the spring member in an axial direction. There are two pairs of sets of strut members, one of which is indicated by the numeral 27 being disposed centrally of the spring member 23 and the other pair 28 being disposed peripherally of the spring member 23. Each of the strut members which make up either one of the pairs is disposed at opposite sides of the axis of the spring member, as can be best seen by reference to FIGS. 3 and 5.

The individual strut members of each set extend in the same general plane parallel to the axis of the spring member 23. For example, the individual strut members indicated by the numerals 29 shown in FIG. 3 extend in a same general plane parallel to the axis of the spring member 23 and are located adjacent the periphery of the spring member 23 at the edge nearest the viewer. It will be noted that each of the strut members 29 extend parallel to each other, and each is disposed at a slight angle to the axis of the spring member 23. The ends of each of the strut members 29 are spaced axially and circumferentially of each other relative to the spring member 23 so that upon compression of the spring member 23 they will become oriented as shown in FIG. 8.

The pair of centrally disposed sets of strut members which has been identified by the numeral 27 are likewise disposed at opposite sides of the axis of the spring member 23. Each of the individual strut members indicated by the numeral 30 of the pair 27 is likewise parallel to each of the other individual strut members in its set at the same side of the axis of the spring member and each is parallel to each other. Each of the individual strut members in a given set extends at a slight angle to the axis of the spring member and the ends of each are spaced circumferentially of each other relative to the spring member in the same manner as the strut members disposed at the periphery of the spring member. Thus, upon compression axially of the spring member, each of the strut members tends to urge the individual flights of the spring member 23 radially outwardly so as to increase the diametrical dimensions of that member.

Reference to FIG. 3 shows that the individual flights 24 of the spring member 23 are not truly helical adjacent the strut members which are disposed at the periphery of the spring member 23. For example, it will be noted that the areas of the individual flights 24 immediately adjacent and at each side of the individual strut members 29 are somewhat flattened from a truly helical shape in order to facilitate molding of the item through the use of cam operated molds.

If it is desired, the spring member 23 may be manufactured with fewer or with no strut members as is shown in FIG. 9. I have found, however, that the use of the strut members provides the most stable wad and provides the most efficient use of material from which the wad is manufactured. Moreover, a more effective diametrical expansion is provided through the use of the strut member.

It will be noted that the tubular wall 26 of the wad shown in FIG. 3 is provided with a plurality of axially extending slits 31. These slits, as best shown in FIG. 4, are diametrically opposed. These slits may or may not be utilized as desired, depending upon the speed with which it is desired that the wad separate from the shot load 18 immediately subsequent to firing of the shell. If it is desired, the slits 31 may be eliminated, but, of course, in that event the individual panels defined by the slits 31 will not be free to turn outwardly and separate from the shot load as quickly subsequent to firing ofthe shell.

FIG. 9 shows an alternative form of the invention wherein the individual strut members have not been included. As indicated hereinbefore, such a structure requires more polyethylene in order to provide the desired spring effect to the spring member 32. In other respects this wad which is indicated generally by the numeral 33 is essentially identical to the wad shown in FIGS. l-8. The spring member functions essentially in the same manner, in that it resists compression and reduces shock and expands diametrically so as to perform a scrubbing operation as it leaves the barrel of the gun while the obturator member 34 and the flange 35 effectively seal the gases generated by the propellant when the latter is ignited.

When shells such as are shown in FIG. 1 are fired, the propellant 15 will be ignited by the firing of the primer 13 and the gases which are rapidly generated as a result thereof force the wad member and the shot load 18 outwardly from the casing 11. The peripheral flange 22 and the obturator member 21 together form an effective seal so as to prevent escape of the gas past the obturator member. The sudden expansion generated by the ignited propellant 15 causes the spring member 23 to be compressed axially because of the mass of shot load 18 which bears against the opposite end of the wad. Such axial compression results in the individual strut members being distorted as shown in FIG. 8, which in turn causes the spring member 23 to expand diametrically and thereby provide a scrubbing action to the barrel wall to limit and minimize lead or powder fouling. At the same time the wad is maintained in a stable orientation relative to the barrel and casing, and a cushion is provided against the shock of firing. It will be readily recognized that because of the inherent resilience of the spring member 23, the length of the wad is sufficiently variable to permit several different loads to be loaded with the same wad size.

If desired, the wad column disclosed and claimed herein may be manufactured from polypropylene, among other materials having sufficient resiliency to provide the desired spring action.

It will, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the parts without departing from the scope of my invention which consists of the matter shown and described herein.

What is claimed is:

l. A wad column for a shotgun shell comprising,

a. an annular obturator member adapted to overlie the propellant when disposed within a shotgun shell,

b. a shot supporting member,

c. a generally helically extending compression spring member integral with said members and disposed therebetween and holding the same in spaced relation, and

d. generally axially extending strut members connecting flights of said spring member in an axial direction between said other members.

2. The structure defined in claim 1 wherein at least some of said strut members extend at an acute angle to the axis of said spring member.

3. The structure defined in claim 1 wherein a plurality of said strut members are arranged in a general plane extending parallel to the axis of said spring member.

4. The structure defined in claim 1 wherein a plurality of said strut members are arranged in a general plane extending parallel to the axis ofsaid spring member but each extends at a slight angle thereto.

5. The structure defined in claim 1 wherein a plurality of said strut members are arranged along a line extending parallel to the axis of said spring member and connect each of the flights thereof to each other and to said obturator and shot supporting members.

6. The structure defined in claim 1 wherein a plurality of said strut members are arranged in a general plane extending parallel to the axis of said spring member and connect each of the flights thereof to each other and to said obturator and shot supporting members, each of said strut members extending at a slight angle to the axis of said spring member.

7. The structure defined in claim 1 wherein said strut members are disposed on opposite sides of the axis of said spring member and are arranged along planes extending generally parallel thereto.

8. The structure defined in claim 1 wherein said strut members are disposed on opposite sides of the axis of said spring member and are arranged alone planes extending generally parallel thereto, each of said strut members extending at a slight angle to the axis of said spring member and being arranged to cause said spring member to expand radially upon compression thereof.

9. The structure defined in claim 1 wherein said strut members are disposed immediately adjacent to and on opposite sides of the axis of said spring member and are arranged along planes extending generally parallel thereto.

10. The structure defined in claim 1 wherein said strut members are disposed immediately adjacent to and on 0pposite sides of the axis of said spring member and are arranged along planes extending generally parallel thereto, each of said strut members extending at a slight angle to the axis of said spring member.

11. The structure defined in claim 1 wherein said strut members are disposed on opposite sides of the axis of said spring members and are arranged along planes extending generally parallel thereto, each of said strut members extending in a given plane at one side of the axis of said spring member being generally parallel to the other strut members in said plane.

12. The structure defined in claim 1 wherein said strut members are disposed on opposite sides of the axis of said spring member and are arranged along planes extending generally parallel thereto, each of said strut members extending at a slight angle to the axis of said spring member and being arranged to cause said spring member to expand radially upon compression thereof, each of said strut members extending in a given plane at one side of the axis of said spring member being generally parallel to the other strut members in said plane at said side.

13. The structure defined in claim 1 wherein a set consisting of a plurality of said strut members are arranged in a plane extending generally parallel to the axis of said spring member and wherein another set consisting of a plurality of said strut members are arranged in the same general plane but at opposite sides of said spring member, said sets of strut members being spaced radially outwardly from the axis of said spring member.

14. The structure defined in claim 13 wherein each of said strut members extends inwardly from the outer periphery of said spring member.

15. The structure defined in claim 13 wherein each of said strut members extends inwardly and generally radially from the outer periphery of said spring member.

16. The structure defined in claim 13 wherein each of said strut members extends generally radially of said spring member.

17. The structure defined in claim 13 wherein each of said strut members of each of said sets extends at a slight angle to the axis of the said spring member and generally parallel to each other strut member in that set.

18. The structure defined in claim 13 wherein each of said strut members of each of said sets extends at a slight angle to the axis of said spring member and generally parallel to each other in that set, each of said struts extending from its end adjacent said obturator member toward its end adjacent said shot contacting member in the same circumferential direction.

19. A wad column for a shotgun shell comprising,

a. an annular obturator member adapted to overlie the propellant when disposed within a shotgun shell,

b. a shot supporting member,

c. a generally helically extending compression spring member integral with said members and disposed therebetween said holding the same in spaced relation,

d. a plurality of sets of generally axially extending strut members connecting the flights of said spring member to each other and to said obturator and shot supporting members,

e. each set of said strut members extending in a general plane passing through the axis of said spring member and being comprised of a plurality of individual strut members, each of which extends at a slight angle to the axis of said spring member and parallel to each of the other strut members in that set,

f. a pair of said sets of strut members extending in the same general diametric plane and being disposed at opposite sides of the axis of said spring member, and

g. each of said strut member being constructed and arranged to cooperate with the other of said strut members to urge the flights of said spring member radially outwardly upon compression of said spring member.

20. The structure defined in claim 19 wherein a second pair of said sets of strut members extends in a single general diametric plane disposed substantially normally to the general diametric plane in which said first pair of sets of strut members extend.

21. The structure defined in claim 20 wherein one of said pairs of strut members is disposed adjacent the axis of said spring member and the other pair of said strut members is disposed adjacent the periphery of said spring member.

22. The structure defined in claim 19 wherein each of said strut members has opposite ends spaced axially of said spring member, one end of each of said strut members being spaced from its other end circumferentially of said spring member.

23. The structure defined in claim 20 wherein one of said pairs of strut members is disposed adjacent the axis of said spring member and the other pair of said strut members is disposed adjacent the periphery of said spring member, each of said pairs of strut members being spaced radially of the other.

24. The structure defined in claim 19 wherein said spring member merges with said obturator member and said shot supporting member at each of its ends.

25. A wad column for a shotgun shell comprising,

a. an annular obturator member for overlying the propellant,

b. a shot supporting member, and

c. a generally helically extending compression spring member disposed between said members and holding the same in spaced relation.

26. The structure defined in claim 25 wherein said shot supporting member is comprised of a shot pouch.

27. The structure defined in claim 25 wherein said obturator member is comprised of an annular disc having a peripheral flange extending axially away from said spring member.

28. The structure defined in claim 25 wherein said members are formed of molded polyethylene.

29. The structure defined in claim 25 wherein said members in their free form have equal diameters and said spring member increases its diametric dimensions upon axial compression thereof.

30. The structure defined in claim 1, and

e. a base,

f. a primer within said base,

g. a casing secured to said base and surrounding said obturator member in close fitting relation,

h. a propellant disposed between said primer and said obturator member in position to be ignited by said primer when the latter is fired,

i. a shot load supported by said shot supporting member within said casing, and

j. means for releasably retaining said shot load within said casing until said prgpel lani is ignited by said primer. 

1. A wad column for A shotgun shell comprising, a. an annular obturator member adapted to overlie the propellant when disposed within a shotgun shell, b. a shot supporting member, c. a generally helically extending compression spring member integral with said members and disposed therebetween and holding the same in spaced relation, and d. generally axially extending strut members connecting flights of said spring member in an axial direction between said other members.
 2. The structure defined in claim 1 wherein at least some of said strut members extend at an acute angle to the axis of said spring member.
 3. The structure defined in claim 1 wherein a plurality of said strut members are arranged in a general plane extending parallel to the axis of said spring member.
 4. The structure defined in claim 1 wherein a plurality of said strut members are arranged in a general plane extending parallel to the axis of said spring member but each extends at a slight angle thereto.
 5. The structure defined in claim 1 wherein a plurality of said strut members are arranged along a line extending parallel to the axis of said spring member and connect each of the flights thereof to each other and to said obturator and shot supporting members.
 6. The structure defined in claim 1 wherein a plurality of said strut members are arranged in a general plane extending parallel to the axis of said spring member and connect each of the flights thereof to each other and to said obturator and shot supporting members, each of said strut members extending at a slight angle to the axis of said spring member.
 7. The structure defined in claim 1 wherein said strut members are disposed on opposite sides of the axis of said spring member and are arranged along planes extending generally parallel thereto.
 8. The structure defined in claim 1 wherein said strut members are disposed on opposite sides of the axis of said spring member and are arranged alone planes extending generally parallel thereto, each of said strut members extending at a slight angle to the axis of said spring member and being arranged to cause said spring member to expand radially upon compression thereof.
 9. The structure defined in claim 1 wherein said strut members are disposed immediately adjacent to and on opposite sides of the axis of said spring member and are arranged along planes extending generally parallel thereto.
 10. The structure defined in claim 1 wherein said strut members are disposed immediately adjacent to and on opposite sides of the axis of said spring member and are arranged along planes extending generally parallel thereto, each of said strut members extending at a slight angle to the axis of said spring member.
 11. The structure defined in claim 1 wherein said strut members are disposed on opposite sides of the axis of said spring members and are arranged along planes extending generally parallel thereto, each of said strut members extending in a given plane at one side of the axis of said spring member being generally parallel to the other strut members in said plane.
 12. The structure defined in claim 1 wherein said strut members are disposed on opposite sides of the axis of said spring member and are arranged along planes extending generally parallel thereto, each of said strut members extending at a slight angle to the axis of said spring member and being arranged to cause said spring member to expand radially upon compression thereof, each of said strut members extending in a given plane at one side of the axis of said spring member being generally parallel to the other strut members in said plane at said side.
 13. The structure defined in claim 1 wherein a set consisting of a plurality of said strut members are arranged in a plane extending generally parallel to the axis of said spring member and wherein another set consisting of a plurality of saId strut members are arranged in the same general plane but at opposite sides of said spring member, said sets of strut members being spaCed radially outwardly from the axis of said spring member.
 14. The structure defined in claim 13 wherein each of said strut members extends inwardly from the outer periphery of said spring member.
 15. The structure defined in claim 13 wherein each of said strut members extends inwardly and generally radially from the outer periphery of said spring member.
 16. The structure defined in claim 13 wherein each of said strut members extends generally radially of said spring member.
 17. The structure defined in claim 13 wherein each of said strut members of each of said sets extends at a slight angle to the axis of the said spring member and generally parallel to each other strut member in that set.
 18. The structure defined in claim 13 wherein each of said strut members of each of said sets extends at a slight angle to the axis of said spring member and generally parallel to each other in that set, each of said struts extending from its end adjacent said obturator member toward its end adjacent said shot contacting member in the same circumferential direction.
 19. A wad column for a shotgun shell comprising, a. an annular obturator member adapted to overlie the propellant when disposed within a shotgun shell, b. a shot supporting member, c. a generally helically extending compression spring member integral with said members and disposed therebetween said holding the same in spaced relation, d. a plurality of sets of generally axially extending strut members connecting the flights of said spring member to each other and to said obturator and shot supporting members, e. each set of said strut members extending in a general plane passing through the axis of said spring member and being comprised of a plurality of individual strut members, each of which extends at a slight angle to the axis of said spring member and parallel to each of the other strut members in that set, f. a pair of said sets of strut members extending in the same general diametric plane and being disposed at opposite sides of the axis of said spring member, and g. each of said strut member being constructed and arranged to cooperate with the other of said strut members to urge the flights of said spring member radially outwardly upon compression of said spring member.
 20. The structure defined in claim 19 wherein a second pair of said sets of strut members extends in a single general diametric plane disposed substantially normally to the general diametric plane in which said first pair of sets of strut members extend.
 21. The structure defined in claim 20 wherein one of said pairs of strut members is disposed adjacent the axis of said spring member and the other pair of said strut members is disposed adjacent the periphery of said spring member.
 22. The structure defined in claim 19 wherein each of said strut members has opposite ends spaced axially of said spring member, one end of each of said strut members being spaced from its other end circumferentially of said spring member.
 23. The structure defined in claim 20 wherein one of said pairs of strut members is disposed adjacent the axis of said spring member and the other pair of said strut members is disposed adjacent the periphery of said spring member, each of said pairs of strut members being spaced radially of the other.
 24. The structure defined in claim 19 wherein said spring member merges with said obturator member and said shot supporting member at each of its ends.
 25. A wad column for a shotgun shell comprising, a. an annular obturator member for overlying the propellant, b. a shot supporting member, and c. a generally helically extending compression spring member disposed between said members and holding the same in spaced relation.
 26. The structure defined in claim 25 wherein said shot supporting member is comprised of a shot pouch.
 27. The structure defined in claim 25 wherein said obturator member is comprised of an annular disc having a peripheral flange extending axially away from said spring member.
 28. The structure defined in claim 25 wherein said members are formed of molded polyethylene.
 29. The structure defined in claim 25 wherein said members in their free form have equal diameters and said spring member increases its diametric dimensions upon axial compression thereof.
 30. The structure defined in claim 1, and e. a base, f. a primer within said base, g. a casing secured to said base and surrounding said obturator member in close fitting relation, h. a propellant disposed between said primer and said obturator member in position to be ignited by said primer when the latter is fired, i. a shot load supported by said shot supporting member within said casing, and j. means for releasably retaining said shot load within said casing until said propellant is ignited by said primer. 